In this study, we addressed the problem of the spatial variability of plough layer compaction by high-power and no-tillage multifunction units in the management of maize planting in the Great Northern Wilderness in China. A comprehensive field experiment involving high-power and no-tillage multifunction units for 165 acres of maize was conducted and analyzed using GIS. Firstly, the test area was divided into four areas, and points were set at equal horizontal distances to collect data on the compactness, water content, porosity and fatigue of the plough layer at different depths. Secondly, the GIS kriging difference method was used to analyze the impact of longitudinal compaction of the plough layer profile at each depth in different test areas. Thirdly, the GIS kriging difference method was used to analyze the lateral spatial distribution of plough layer compaction. Finally, the spatial longitudinal and transverse variabilities of the plough layer were summarized, and the effect of the high-power and no-tillage multifunction units on the physical ecology of the soil in the plough layer was investigated. The results show that the physical properties of the plough layer can be significantly affected by compaction after spreading in the middle tillage period. The surface soil was most affected, with the greatest change in compactness and porosity; the rate of change of soil compactness reached 143.49% and the rate of change of soil porosity reached 40.57%. With the increase in soil depth, the rate of change of soil compactness and porosity gradually decreased. The greatest variation in soil moisture content was found in the middle layer and reached a maximum of 13.78% at a depth of approximately 20 cm. The results of the spatial variability analysis show that the mean values of c₀/(c₀ + c) for the spatial semi-variance functions of compactness, water content and porosity of the tilled soil in the longitudinal space of each test area before compaction were approximately 15%, 19% and 20%, respectively; after compaction, the mean values were approximately 33%, 23% and 30%, respectively; the mean values of c₀/(c₀ + c) for the spatial semi-variance functions of compactness, water content and porosity change of the tilled soil were approximately 24%, 14% and 12%, respectively. The mean values of c₀/(c₀ + c) for the spatial semi-variance functions of compactness, water content and porosity of the soil at each depth in the lateral space before compaction were approximately 80%, 71% and 78%, respectively, and after compaction the mean values were approximately 40%, 23% and 24%, respectively, with the mean values of c₀/(c₀ + c) along the east–west direction being approximately 8%, 27% and 18%, and the mean values of c₀/(c₀ + c) along the north–south direction being approximately 9%, 0% and 20%. The results show that compaction by high-power and no-tillage multifunction units led to a decrease in the spatial variability of soil physical parameters at each depth of tillage in the black soil layer in the longitudinal space, while the spatial variability of the soil physical parameters at each depth of tillage in the black soil layer in the transverse space increased. Moreover, the degree of influence of compaction by high-power and no-tillage multifunction units on soil physical parameters was higher in both vertical and horizontal spaces. This study can provide a theoretical reference for the analysis of the impact of large units on the compaction of black soil layers from the perspective of GIS.

Soil compaction leads to crop yield reduction in Northeast of China. The interaction mechanism of driver-agricultural machinery-black soil is not clear. A comprehensive field experiment of 4 hm2 of maize seeding was carried out in Baiquan County Cooperative. The results showed that the average increase rates of soil compaction before and after sowing were 118.82% and 71.02%. The SEM showed that waist fatigue had the greatest impact on soil compaction, and the unit fatigue of waist caused 1.51 and 1.27 unit compactions to the soil at the depths of 10 cm and 20 cm. The neck, waist, arm and leg fatigue of drivers increased the surface soil compaction by 1.83, 1.76, 1.78 and 1.55 units, and the deep soil compaction by 1.65, 1.58, 1.60 and 1.40 units. The results can provide a reference for the integration of human factor efficiency and conservation tillage. Keywords: agriculture ergonomics, structural equation model, black soil compaction, sowing, high-power tractor DOI: 10.25165/j.ijabe.20231604.7284 Citation: Yang X, Zhai Z Q, Guo W J, Li W J, Yang M L, Song Z H. Analysis of black soil compaction with driver-agricultural machinery-soil system under corn sowing with high-power tractor in Northeast China. Int J Agric & Bio Eng, 2023; 16(4): 168-173

Plowing operations can improve the quality of the shallow soil layer, but plowing tractors still cause compaction effects on the deeper soil layers. The temporal and spatial accumulation of compaction effects can hinder crop growth, thereby reducing the overall efficiency of plowing operations and creating obstacles to soil ecological health. It is urgent to address the bottlenecks in mechanized ecological operations. This paper addresses the unclear mechanical effects of heavy-duty tractor tillage equipment on soil compaction in the tillage layer. By integrating and constructing a ''heavy-duty tractor-tillage layer soil'' system dynamics coupling model, it identifies the primary influencing factors of joint tillage operations on soil compaction in the tillage layer and explores the response patterns of tillage equipment parameters to the soil compaction process. The research results indicate that as the number of compaction operations increases, soil compaction increases, and soil stress transmission shows a gradually decreasing trend; when the tillage unit's operating speed is 3 km/h, the soil stress at a depth of 10 cm can reach a maximum of 499.2 kPa; when the operating speed is 6 km/h, the soil stress at a depth of 10 cm reaches a maximum of 469.1 kPa; when the operating speed is 9 km/h, the soil stress at a depth of 10 cm reaches a maximum of 438.8 kPa; when the acceleration and longitudinal acceleration increase, soil stress correspondingly increases; when the direction of lateral acceleration changes, the center of gravity of the tractor shifts, and the trends in soil stress on the inner and outer sides of the tires are opposite. The research findings can provide theoretical references for improving the operational efficiency of the unit and the development of black soil protection and utilization technologies.

Tractor driver psychological load evolution paradigm and experimental verification